Identified the problem with my Honda 5hp outboard

[Tom G P 21]

I have a Honda 5hp outboard that I bought new 10 years ago shortly after buying my boat. Last year it was giving me problems when I had to run it for long periods of time. I thought it was the carburetor flooding. I even replaced the carburetor last year thinking that I fixed the problem. Turns out I was wrong, it was still running miserably this year. Doing some troubleshooting found the engine ran fine with the cover off but sputtered with it on. The engine forums all pointed to an exhaust leak and that this was a common problem with the small water cooled Honda engines. Went back out to the boat ran it again and found this pictured below. The exhaust manifold corroded and leaking into the cowling. Short term fix is to run the engine with the cover off in order to finish the season. Long term is to replace the exhaust manifold. The part is still available.  Unfortunately in order to get at the bolts the power head has to come off (thank you Honda). I can do small repairs but this is a little above my skill level, might need to get quotes or check with some of my gear head friends.

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[Captain Kidd]

You might want to do a search and see if you can find a video that will walk you through it. If money isn't an issue, pay someone.

(photo tip: don't forget to hit the insert button)

[Tom G P 21]

Thanks, found the insert button. I had tried several times to do that but was missing that step.

[Eddie C]

In the interim, I would consider patching it with Marine Tex. Many years ago my Dad patched the exhaust manifold on a 4 cylinder I/O and it held for a few years.